Pruritus - Generalized Differential Diagnosis Algorithm - Systemic and Primary Causes

== Primary Skin Lesions ==

Macules / Papules / Plaques:

 • Xerosis (dry skin)

 • Atopic dermatitis

 • Nummular dermatitis

 • Seborrheic dermatitis

 • Stasis dermatitis

 • Psoriasis

 • Lichen Planus

 • Infestations (scabies, lice)

 • Arthropod bites

Vesicles/Bullae:

 • Varicella zoster (chickenpox)

 • Dermatitis herpetiformis

 • Bullous pemphigoid

Wheals/Hives:

 • Urticaria

== No Primary Skin Lesion / Systemic ==

Blood Glucose:

 • Diabetes Mellitus

Liver Function Tests/Enzymes:

 • Cholestatic liver disease

Creatinine & BUN:

 • Chronic renal failure/uremia

TSH & T4:

 • Hypothyroidism

 • Hyperthyroidism

CBC & Differential:

 • Lymphoma

 • Leukemia

 • Polycythemia rubra vera

 • Essential Throbocythemia

 • Myelodisplastic syndrome

Psychiatric Disease:

 • Delusions of parasitosis



#Pruritus #primary #secondary #systemic #generalized #dermatology #Differential #Diagnosis #Algorithm #causes